Indian researchers are prioritizing the development and validation of indigenous diagnostic assays for COVID-19 testing to reduce dependence on other countries. The Indian Council of Medical Research (ICMR) has revealed that they validated and recommended 11 RT-PCR based indigenous assays for the testing of COVID-19.
The limited supply of diagnostic kits for COVID-19 diagnosis is a matter of concern when the number of confirmed cases is increasing. Indigenous production of testing kits and their validation has become necessary to meet the increasing demand for diagnostic devices. In a country like India, which has a population load of more than 130 crores, indigenous production of diagnostic kits and its uninterrupted availability could be a game-changer.
Earlier, the indigenous TrueNat assay for Tuberculosis was validated by ICMR. The test is an accurate and reliable method for quick screening of TB patients and is a WHO pre-qualified test. ICMR-National Institute of Virology (NIV) had validated the TrueNat assay as a point of care test for Nipah virus disease.
The TrueNat assay was also developed to screen COVID-19 patients by an indigenous manufacturer in April 2020. ICMR validated the Indian made TrueNat based COVID-19 testing, and several states already initiated using the test for SARS-CoV-2 detection. The states have conducted more than 1.3 lakh screening tests since April 2020. However, the lack of TrueNat confirmatory assay has been a rate-limiting step. RT-PCR based tests have to confirm all TrueNat positive samples.
ICMR recently validated an RdRp gene-based confirmatory assay of TrueNat, developed by an indigenous manufacturer. The test was found to have high specificity and sensitivity. The Department of Health Research (DHR)/ICMR Virus Research and Diagnostic Laboratory (VRDL) at Bangalore Medical College and Research Institute, Bengaluru, strictly conducted the validations for both the tests.
The TrueNat COVID-19 test is now recommended by ICMR as a two-step test: E-gene screening assay as a preliminary screening test and RdRp-based test as a confirmatory test.
An affordable and reliable option to increase the COVID-19 testing capacity of India is offered by this fully indigenous diagnostic platform. The platform includes an inbuilt RNA extraction system, a TrueNat machine, collection swabs, viral lysis medium (VLM), and RT-PCR chips. A total of 12-48 samples can be tested per day, with a single assay taking 35-50 minutes for 1-4 samples.
The samples are collected in VLV, which inactivates the virus, requiring minimal biosafety and biosecurity measures. Even the primary health centers or district hospitals can carry out these Indian made COVID-19 tests.